###########################################################################
#
# docsave.pm
# A component of the Greenstone digital library software
# from the New Zealand Digital Library Project at the 
# University of Waikato, New Zealand.
#
# Copyright (C) 1999 New Zealand Digital Library Project
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
#
###########################################################################

# This document processor saves a document in the 
# archives directory of a collection


package docsave;

use arcinfo;
use docproc;
use util;


sub BEGIN {
    @ISA = ('docproc');
}

sub new {
    my ($class, $collection, $archive_info, $verbosity, 
	$gzip, $groupsize, $outhandle) = @_;
    my $self = new docproc ();
    
    
    $groupsize=1 unless defined $groupsize;
    $self->{'collection'} = $collection;
    $self->{'archive_info'} = $archive_info;
    $self->{'verbosity'} = $verbosity;
    $self->{'gzip'} = $gzip;
    
    $self->{'groupsize'} = $groupsize;
    $self->{'gs_count'} = 0;

    # keep an associate array of all metavalues used by collection to
    # help generate the XML DTD 
    $self->{'dtd_metadata'} = {}; 

    $self->{'outhandle'} = STDERR;
    $self->{'outhandle'} = $outhandle if defined $outhandle;
    # set a default for the archive directory
    $self->{'archive_dir'} = &util::filename_cat ($ENV{'GSDLCOLLECTDIR'}, "archives");
    
    $self->{'sortmeta'} = undef;
    
    return bless $self, $class;
}

sub setarchivedir {
    my $self = shift (@_);
    my ($archive_dir) = @_;
    
    &util::mk_all_dir ($archive_dir) unless -e $archive_dir;
    $self->{'archive_dir'} = $archive_dir;
}

sub set_sortmeta {
    my $self = shift (@_);
    my ($sortmeta) = @_;
    
    $self->{'sortmeta'} = $sortmeta;
}

sub process {
    my $self = shift (@_);
    my ($doc_obj) = @_;
 
    my $outhandle = $self->{'outhandle'};
   
    if ($self->{'groupsize'} > 1) {
	$self->group_process ($doc_obj);
	
    } else {
	# groupsize is 1 (i.e. one document per GML file) so sortmeta 
	# may be used
	
	my $OID = $doc_obj->get_OID();
	$OID = "NULL" unless defined $OID;
	
	# get document's directory
	my $doc_dir = $self->get_doc_dir ($OID);
	
	# copy all the associated files, add this information as metadata
	# to the document
	$self->process_assoc_files ($doc_obj, $doc_dir);
	
	my $doc_file 
	    = &util::filename_cat ($self->{'archive_dir'}, $doc_dir, "doc.gml");
	my $short_doc_file = &util::filename_cat ($doc_dir, "doc.gml");
	
	if (!open (OUTDOC, ">$doc_file")) {
	    print $outhandle "docsave::process could not write to file $doc_file\n";
	    return;
	}

	# save this document
	$doc_obj->output_section('docsave::OUTDOC', 
				 $doc_obj->get_top_section(),
				 $self->{'collection'},
				 $self->{'dtd_metadata'},0);

	close OUTDOC;

	if ($self->{'gzip'}) {
	    my $doc_file = $self->{'gs_filename'};
	    `gzip $doc_file`;
	    $doc_file .= ".gz";
	    $short_doc_file .= ".gz";
	    if (!-e $doc_file) {
		print $outhandle "error while gzipping: $doc_file doesn't exist\n";
		return 0;
	    }
	}

	# do the sortmeta thing
	my ($metadata);
	if (defined ($self->{'sortmeta'})) {
	    $metadata = $doc_obj->get_metadata_element ($doc_obj->get_top_section(), $self->{'sortmeta'});
	}

	# store reference in the archive_info
	$self->{'archive_info'}->add_info($OID, $short_doc_file, $metadata);
    }
}

sub group_process {
    my $self = shift (@_);
    my ($doc_obj) = @_;
    
    my $outhandle = $self->{'outhandle'};

    my $OID = $doc_obj->get_OID();
    $OID = "NULL" unless defined $OID;

    my $groupsize = $self->{'groupsize'};
    my $gs_count = $self->{'gs_count'};
    my $open_new_file = (($gs_count % $groupsize)==0);

    # opening a new file, or document has assoicated files => directory needed
    if (($open_new_file) || (scalar(@{$doc_obj->get_assoc_files()})>0)) {

	# get document's directory
	my $doc_dir = $self->get_doc_dir ($OID);

	# copy all the associated files, add this information as metadata
	# to the document
	$self->process_assoc_files ($doc_obj, $doc_dir);


	if ($open_new_file) {
	    # only if opening new file
	    my $doc_file 
		= &util::filename_cat ($self->{'archive_dir'}, $doc_dir, "doc.gml");
	    my $short_doc_file = &util::filename_cat ($doc_dir, "doc.gml");
	    
	    if ($gs_count>0)
	    {
		return if (!$self->close_file_output());
	    }
	    
	    if (!open (OUTDOC, ">$doc_file")) {
		print $outhandle "docsave::group_process could not write to file $doc_file\n";
		return;
	    }
	    $self->{'gs_filename'} = $doc_file;
	    $self->{'gs_short_filename'} = $short_doc_file;
	    $self->{'gs_OID'} = $OID;
	}
    }

    # save this document
    $doc_obj->output_section('docsave::OUTDOC', 
			     $doc_obj->get_top_section(),
			     $self->{'collection'},
			     $self->{'dtd_metadata'},0);

    $self->{'gs_count'}++;
}


sub get_doc_dir {
    my $self = shift (@_);
    my ($OID) = @_;

    my $doc_info = $self->{'archive_info'}->get_info($OID);
    my $doc_dir = "";
    if (defined $doc_info && scalar(@$doc_info) >= 1) {
	# this OID already has an assigned directory, use the
	# same one.
	$doc_dir = $doc_info->[0];
	$doc_dir =~ s/\/?doc\.gml(\.gz)?$//;
    } else {
	# have to get a new document directory
	my $doc_dir_rest = $OID;
	my $doc_dir_num = 0;
	do {
	    $doc_dir .= "/" if $doc_dir_num > 0;
	    if ($doc_dir_rest =~ s/^(.{1,8})//) {
		$doc_dir .= $1;
		$doc_dir_num++;
	    }
	} while ($doc_dir_rest ne "" && 
		 ((-d &util::filename_cat ($self->{'archive_dir'}, "$doc_dir.dir")) || 
		  ($self->{'archive_info'}->size() >= 1024 && $doc_dir_num < 2)));
	$doc_dir .= ".dir";
	
    }
	
    &util::mk_all_dir (&util::filename_cat ($self->{'archive_dir'}, $doc_dir));

    return $doc_dir;
}


sub process_assoc_files {
    my $self = shift (@_);
    my ($doc_obj, $doc_dir) = @_;

    my $outhandle = $self->{'outhandle'};

    my @assoc_files = ();
    foreach $assoc_file (@{$doc_obj->get_assoc_files()}) {
	my ($dir, $afile) = $assoc_file->[1] =~ /^(.*?)([^\/\\]+)$/;
	$dir = "" unless defined $dir;
	if (-e $assoc_file->[0]) {
	    my $filepath = &util::filename_cat($self->{'archive_dir'}, $doc_dir, $afile);
	    &util::hard_link ($assoc_file->[0], $filepath);
	    $doc_obj->add_utf8_metadata ($doc_obj->get_top_section(),
					 "gsdlassocfile",
					 "$afile:$assoc_file->[2]:$dir");
	    $doc_obj->set_utf8_metadata_element ($doc_obj->get_top_section(),
						 "assocfilepath",
						 "$doc_dir");
	} elsif ($self->{'verbosity'} > 2) {
	    print $outhandle "docsave::process couldn't copy the associated file " .
		"$assoc_file->[0] to $afile\n";
	}
    }
}
    

sub close_file_output
{
    my ($self) = @_;
    
    close OUTDOC;

    my $OID = $self->{'gs_OID'};
    my $short_doc_file = $self->{'gs_short_filename'};

    if ($self->{'gzip'}) {
	my $doc_file = $self->{'gs_filename'};
	`gzip $doc_file`;
	$doc_file .= ".gz";
	$short_doc_file .= ".gz";
	if (!-e $doc_file) {
	    my $outhandle = $self->{'outhandle'};
	    print $outhandle "error while gzipping: $doc_file doesn't exist\n";
	    return 0;
	}
    }

    # store reference in the archive_info
    $self->{'archive_info'}->add_info($OID, $short_doc_file);

    return 1;
}

1;